Non-Invasive Sacral Nerve Stimulation: How External Electrode Therapy Works

Sacral nerve stimulation (SNS) can be a safe and effective way to help relieve the symptoms, discomfort, and pelvic floor dysfunction associated with a range of bladder, bowel, and pelvic floor conditions. Unlike implanted sacral neuromodulation systems that require surgery, non-invasive sacral nerve stimulation uses external skin electrodes to deliver gentle electrical stimulation to the sacral nerves and can be carried out easily at home with the help of Kegel8 devices. This may help improve communication between the nerves, pelvic organs, and pelvic floor muscles to support better bladder and bowel control, reduce urgency and leakage, and help ease pelvic discomfort.

Where Are the Sacral Nerves?

The sacral nerves are located in the lower part of the spine and pelvis. They form part of the sacral plexus — a network of nerves that helps control many important functions in the lower body, including bladder, bowel, pelvic floor, and sexual function.

These nerves travel from the lower back through the pelvis and connect to the bladder, bowel, pelvic floor muscles, sphincters, genitals, legs, and feet. They carry signals between the brain and pelvic organs, helping control sensation, muscle movement, bladder and bowel emptying, and pelvic floor coordination.

Because the sacral nerves play such an important role in pelvic floor function, non-invasive sacral nerve stimulation using external skin electrodes may help support communication between the nerves, pelvic organs, and pelvic floor muscles to help relieve symptoms such as urgency, leakage, pelvic pain, and bladder or bowel dysfunction.

The sacral plexus includes several important nerves, including the sciatic nerve, pudendal nerve, superior gluteal nerve, inferior gluteal nerve, and posterior cutaneous nerve.

What Do the Sacral Nerves Do?

The sacral nerves control many important functions in the lower body, including movement, sensation, bladder and bowel control, sexual function, and pelvic floor coordination. Each nerve within the sacral plexus has a slightly different role:

• Superior gluteal nerve – helps control movement and rotation of the hip and thigh muscles.
• Inferior gluteal nerve – controls the gluteal (buttock) muscles involved in movement and stability.
• Sciatic nerve – the largest nerve in the body, responsible for movement and sensation in parts of the legs, feet, and lower body.
• Posterior cutaneous nerve – provides sensation to areas of the thigh, lower leg, and perineum.
• Pudendal nerve – one of the most important pelvic floor nerves, helping control bladder and bowel function, pelvic floor muscles, and genital sensation. Irritation or dysfunction affecting this nerve may contribute to pelvic pain, bladder symptoms, sexual dysfunction, and difficulties with bowel control.

Because these nerves are closely involved in pelvic floor function, non-invasive sacral nerve stimulation using external skin electrodes may help support communication between the nerves, pelvic organs, and pelvic floor muscles to help improve bladder and bowel control, reduce urgency and leakage, and ease pelvic discomfort.

What is Sacral Nerve Stimulation?

Non-invasive sacral nerve stimulation is a treatment that uses gentle electrical impulses delivered through external skin electrodes to help support communication between the brain, pelvic organs, and pelvic floor nerves. It may help manage symptoms associated with bladder dysfunction, bowel dysfunction, pelvic floor disorders, and some forms of chronic pelvic pain.

The treatment works by stimulating the sacral nerves — the nerves responsible for helping control the bladder, bowel, pelvic floor muscles, and sphincters. By helping regulate these nerve signals, sacral nerve stimulation may help improve bladder and bowel control, reduce urgency and frequency symptoms, and help relieve certain pelvic pain symptoms.

Unlike implanted sacral neuromodulation systems that require surgery, non-invasive sacral nerve stimulation can be carried out easily at home using external electrode pads placed on the skin over the lower back or sacral area. This provides a more accessible and conservative approach to pelvic floor rehabilitation and symptom management.

Sacral nerve stimulation and neuromodulation therapies have been used clinically for many years, with research supporting their safety and effectiveness for selected pelvic floor conditions. NICE approved implanted sacral nerve stimulation therapy in the UK in 2004 for certain bladder and bowel disorders, while non-invasive electrical stimulation therapies are also widely used to support pelvic floor rehabilitation and symptom relief.

Non-invasive sacral nerve stimulation may be used alongside conservative treatments such as pelvic floor physiotherapy, bladder training, medication, and lifestyle changes to help improve pelvic floor function and quality of life.

What Pelvic Floor Conditions Can Sacral Nerve Stimulation Help?

Non-invasive sacral nerve stimulation may help improve symptoms associated with several pelvic floor, bladder, and bowel disorders by supporting communication between the nerves, pelvic organs, and pelvic floor muscles. With Kegel8 devices, this gentle electrical stimulation can be carried out at home using external skin electrodes placed over the sacral area.

Conditions that may benefit from sacral nerve stimulation include:

• Overactive bladder and urinary dysfunction – including urgency, frequency, urinary incontinence, incomplete emptying, and some forms of urinary retention. These symptoms are common after childbirth and menopause, but can affect both women and men.
• Chronic pelvic pain and interstitial cystitis – sacral nerve stimulation may help support relief from pelvic pain symptoms, bladder discomfort, urgency, and irritation associated with painful bladder conditions and pelvic floor dysfunction.
• Faecal incontinence and bowel dysfunction – including bowel urgency, accidental bowel leakage, and some forms of constipation linked to poor pelvic floor coordination or nerve dysfunction.

Because pelvic floor disorders often involve both the muscles and the nervous system, non-invasive sacral nerve stimulation with Kegel8 may help support better pelvic floor control, bladder and bowel function, and overall symptom management alongside other conservative pelvic floor treatments.

Non-Invasive Sacral Nerve Stimulation with Kegel8

Kegel8 devices can help provide non-invasive sacral nerve stimulation using external skin electrodes placed over the lower back or sacral area. In addition to internal pelvic floor stimulation with a vaginal probe, selected Kegel8 devices also include electrode pads that can be used externally to help support pelvic floor rehabilitation, bladder and bowel control, and pelvic comfort.

By delivering gentle electrical impulses to the sacral area, this type of stimulation may help support communication between the nerves, pelvic organs, and pelvic floor muscles. Some users may find this helpful for managing symptoms such as urgency, leakage, pelvic discomfort, or pelvic floor dysfunction.

Kegel8 devices include a range of programmes designed to support pelvic floor therapy and symptom management. The intensity can be adjusted gradually until you can comfortably feel the stimulation without discomfort.

Because the skin over the lower back can be sensitive, always increase the intensity slowly and follow the manufacturer’s instructions carefully. Stimulation should remain comfortable at all times. If you experience discomfort, skin irritation, or burning sensations, stop treatment and reduce the intensity before continuing.

Sources

Besendörfer M, Kohl M, Schellerer V, Carbon R and Diez S (2020) A Pilot Study of Non-invasive Sacral Nerve Stimulation in Treatment of Constipation in Childhood and Adolescence. Front. Pediatr. 8:169. doi: 10.3389/fped.2020.00169

Samejima S, Shackleton C, McCracken L, Malik RN, Miller T, Kavanagh A, et al. (2022) Effects of non-invasive spinal cord stimulation on lower urinary tract, bowel, and sexual functions in individuals with chronic motor-complete spinal cord injury: Protocol for a pilot clinical trial. PLoS ONE 17(12): e0278425. https://doi.org/10.1371/journal.pone.0278425

Pikov V. Vagus Nerve Stimulation and Sacral Nerve Stimulation for Inflammatory Bowel Disease: A Systematic Review. J Transl Gastroenterol. 2023 Oct-Dec;1(2):94-100. doi: 10.14218/jtg.2023.00098. Epub 2023 Dec 25. PMID: 38606364; PMCID: PMC11007757.

Besendörfer, M., Kirchgatter, A., Carbon, R. et al. Sacral neuromodulation for constipation and fecal incontinence in children and adolescents – study protocol of a prospective, randomized trial on the application of invasive vs. non-invasive technique. Trials 25, 210 (2024). https://doi.org/10.1186/s13063-024-08052-6